Factor V Leiden (R506Q) Mutation, Blood
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Factor V Leiden mutation testing should be reserved for patients with clinically suspected thrombophilia and: 1) APC-resistance proven or suspected by a low or borderline APC-resistance ratio, or 2) a family history of factor V Leiden.
Genetics Test Information Provides information that may help with selection of the correct test or proper submission of the test request
Tests for R506Q mutation only.
Special Instructions and Forms Describes specimen collection and preparation information, test algorithms, and other information pertinent to test. Also includes pertinent information and consent forms to be used when requesting a particular test
Direct Mutation Analysis
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Factor V Leiden (R506Q) Mutation, B
Activated protein C (APC) resistance mutation
APC resistance mutation
Factor V Leiden mutation
APC resistance mutation
Factor V Leiden mutation
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Preferred: Yellow top (ACD)
Acceptable: EDTA or sodium citrate
Specimen Volume: Full tube
1. Invert several times to mix blood.
2. Send specimen in original tube.
Additional Information: Can be combined with other molecular coagulation tests;
-61730/MTHAC 5,10-Methylenetetrahydrofolate Reductase A1298C, Mutation, Blood
-81742/PTNT Prothrombin G20210A Mutation, Blood
-81648/MTHFR 5,10-Methylenetetrahydrofolate Reductase C677T, Mutation, Blood
-61367/MTHP 5,10-Methylenetetrahydrofolate Reductase C677T and A1298C Mutations, Blood
1. Coagulation Patient Information Sheet (Supply T675) in Special Instructions
2. New York Clients-Informed consent is required. Please document on the request form or electronic order that a copy is on file. An Informed Consent for Genetic Testing (Supply T576) is available in Special Instructions.
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
1 mL blood in a 3-mL ACD tube
Mild OK; Gross OK
Mild OK; Gross OK
Green top (heparin) tube
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
|Whole blood||Ambient (preferred)||7 days|
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Venous thromboembolism includes deep vein thrombosis and its complication, pulmonary embolism. Plasma from 12% to 20% of venous thromboembolism patients is resistant to the anticoagulant effect of activated protein C (APC resistance). Essentially all patients with hereditary APC resistance have a single nucleotide mutation of the coagulation factor V (fV) gene (F5 rs6025), which encodes for an arginine (R) to glutamine (Q) substitution at position 506 of the factor V protein (fV R506Q). The factor V Leiden (R506Q) gene mutation test is a direct mutation analysis of patient blood leukocyte genomic DNA.
We recommend the coagulation-based activated protein C (APC)-resistance ratio (mixing with factor V-deficient plasma) as the initial screening assay for APC-resistance. Depending on the assay system, the APC-resistance ratio may be indeterminate for patients with a lupus anticoagulant or extremely high heparin levels.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
The interpretive report will include specimen information, assay information, background information, and conclusions based on the test results (normal, heterozygous fV R506Q, homozygous fV R506Q).
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
This direct mutation analysis will not detect individuals with activated protein c (APC)-resistance caused by mechanisms other than the fV R506Q.
Special Coagulation Clinic and/or Medical Genetics consultations are available for DNA diagnosis cases, and may be especially helpful in complex cases or in situations where the diagnosis is atypical or uncertain.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Dahlback B, Carlsson M, Svensson PR: Familial Thrombophilia due to a previously unrecognized mechanism characterized by poor anticoagulant response to activated protein C: prediction of a cofactor to activated protein C. Proc Natl Acac Sci USA 1993;90:1004-1008
2. Bertina RM, Koeleman BP, Koster T, et al: Mutation in blood coagulation factor V associated with resistance to activated protein C. Nature 1994;369:64-67
3. Zoller B, Svensson PJ, He X, Dahlback B: Identification of the same factor V gene mutation in 47 out of 50 thrombosis-prone families with inherited resistance to activated protein C. J Clin Invest 1994;94:2521-2524
4. Hall JG, Eis PS, Law SM, et al. Sensitive detection of DNA polymorphisms by the serial invasive signal amplification reaction. Proc Natl Acad Sci USA 2000;97:8272-8277
5. Heit JA: Thrombophilia: clinical and laboratory assessment and management. In Consultative Hemostasis and Thrombosis. Fourth edition. Edited by CS Kitchens, BM Alving, CM Kessler. Saunders 2012
Method Description Describes how the test is performed and provides a method-specific reference
Direct mutation analysis using PCR amplification, signal generation and release by cleavage of sequence-specific alleles.(Invader Factor V, Invader Plus Chemistry, Hologic, Madison, WI)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday; 12 p.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Extracted DNA and whole blood stored 2 weeks
Performing Laboratory Location The location of the laboratory that performs the test
Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements.
CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
81241-F5 (coagulation factor V) (eg, hereditary hypercoagulability) gene analysis, Leiden variant
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
|Result ID||Reporting Name||LOINC Code|
|21838||Factor V Leiden (R506Q) Mutation, B||21667-1|
|21841||F5DNA Reviewed By||In Process|